I have the BenQ, I've actually never heard of "IIYAMA", maybe just me, I don't know. But I own a BenQ XL2420T and it's an incredible monitor. If gaming in 3d it will also support light boost, not sure about that other one. 120Hz to me makes a big difference in some games, but I would definitely say go with the BenQ, great products, it is an amazing monitor, good picture, tweak it a bit for even better results.